The present invention relates to optical transport systems.
The exponential internet traffic growth projections place enormous transmission rate demand on the underlying information infrastructure at every level. As the response, the 100 Gb/s Ethernet (100 GbE) standard has been adopted recently (IEEE 802.3ba), and 400 GbE and 1 Tb/s Ethernet (1 TbE) are currently under study. Terabit optical Ethernet technologies will be affected by limited bandwidth of information-infrastructure, high energy consumption, and heterogeneity of optical networking infrastructure. To reach beyond 1 Tb/s serial date rates, a huge signal constellation sizes are required for polarization-division multiplexed (PDM) single-carrier QAM systems, with commercially achievable symbol rates. Furthermore, in the context of high-speed optical communication systems, not only the performance of advanced coded modulation schemes but also their complexity plays a crucial role. In addition, security issues of the future optical networks should be addressed rather than later. Thus, such schemes need to be designed meticulously to address both issues simultaneously and in and effective manner.